I don't see how the nose -bar measurement has much meaning at all. It doesn't take into account newer saddles by ISM (noseless, though it appears to have a nose) or Selle SMP (on which important bits ride forward of the nose); nor does it seem to take into account saddles with long noses (Brooks) vs saddles with shorter noses.

Yeah, you can compute things using the measurement. It's just that the calculations are likely to be invalid.

I very much appreciate CC's providing the tool at no cost, but you need to remember it's just a guide. For example, I rode a bike with 'competitive' measurements for for several years, but I didn't ride it much, because it felt wrong. I got a bigger bike, and my mileage went up about 300% ... that data is a hell of a lot more significant than the numbers the tool provides.